Embun

Embun is the term used in Malay and Indonesian to refer to dew, the tiny droplets of water that form on surfaces when water vapor in the air condenses.

Formation occurs when surfaces cool at night and radiate heat to the sky, causing their temperature to fall below the surrounding air’s dew point. Under these conditions, water vapor condenses on surfaces such as leaves, grass, windows, or metal. If temperatures drop below freezing, the condensed water can freeze, producing frost (embun beku or frost crystals) instead of liquid droplets.

Dew is most common on clear, calm nights with high humidity, and its presence depends on surface properties, including texture and color, as well as microclimate factors like wind speed and radiant cooling. Surfaces that are rough or dark tend to collect more dew, while wind can reduce or redistribute condensation. Dew appears primarily in the early morning and may disappear after sunrise as temperatures rise.

Ecological and practical aspects vary by region. Dew provides a source of moisture for some plants and ground-dwelling organisms, particularly in arid or semi-arid environments. It can influence agricultural practices by affecting leaf wetness duration, which in turn affects the risk of fungal diseases. In addition, dew is sometimes collected as a supplemental water source in water-scarce areas using fog nets or dew collectors.

Measurement and study of dew involve concepts such as dew point and leaf wetness, with sensors and observations used in meteorology and agriculture to estimate moisture availability and its effects on ecosystems and crops.